These worked just fine for me. I compared them side by side with my medical grade strips from the hospital. There was the very occasional odd duck in the pack that didn't work, but it was maybe 2 of 100 strips.

This is the first time I've ordered them here but they work fine for me. I've used them in the past. Never had a problem with this brand. Will buy again when I run out. They really help me to determine which foods my body can withstand. I like to test myself after eating something I suspect might be higher carb than the nutritional labels say for instance...low carb bagels and sugar free snacks. I've never had one fail....I'm always burning fat at different degrees :)